Merge branch 'following-relationships-optimizations' into 'develop'

FollowingRelationship storage & performance optimizations

See merge request pleroma/pleroma!2332

diff --cc lib/pleroma/user.ex
Simple merge

diff --cc lib/pleroma/web/activity_pub/transmogrifier.ex
Simple merge

diff --cc lib/pleroma/web/common_api/common_api.ex
Simple merge

diff --cc lib/pleroma/web/mastodon_api/views/account_view.ex
Simple merge

diff --cc test/user_test.exs
Simple merge

diff --cc test/web/activity_pub/transmogrifier_test.exs
Simple merge

diff --cc test/web/common_api/common_api_test.exs
Simple merge

diff --cc test/web/streamer/streamer_test.exs
Simple merge